Silkie chicken questions

[Maverick v]

I recently bought 3 silkies, was told all were hens, one splash 2 black, the 2 black started crowing so I assumed they were roosters, I don't have a need for so many roos so I got rid of one, then the splash started crowing and fighting my black roo, I'm beginning to think she was a roo the whole time, but I've seen so many story's of people believing the have a roo as well till it lays an egg, help

 

[nuthatched]

They are cockerels. Off they go.